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1.
Nat Immunol ; 17(8): 956-65, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27376470

RESUMO

During T cell development, multipotent progenitors relinquish competence for other fates and commit to the T cell lineage by turning on Bcl11b, which encodes a transcription factor. To clarify lineage commitment mechanisms, we followed developing T cells at the single-cell level using Bcl11b knock-in fluorescent reporter mice. Notch signaling and Notch-activated transcription factors collaborate to activate Bcl11b expression irrespectively of Notch-dependent proliferation. These inputs work via three distinct, asynchronous mechanisms: an early locus 'poising' function dependent on TCF-1 and GATA-3, a stochastic-permissivity function dependent on Notch signaling, and a separate amplitude-control function dependent on Runx1, a factor already present in multipotent progenitors. Despite their necessity for Bcl11b expression, these inputs act in a stage-specific manner, providing a multitiered mechanism for developmental gene regulation.


Assuntos
Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Fator de Transcrição GATA3/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Fator 1-alfa Nuclear de Hepatócito/metabolismo , Linfopoese/genética , Receptores Notch/metabolismo , Proteínas Repressoras/metabolismo , Linfócitos T/fisiologia , Proteínas Supressoras de Tumor/metabolismo , Animais , Diferenciação Celular/genética , Linhagem da Célula/genética , Rastreamento de Células , Células Cultivadas , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Fator de Transcrição GATA3/genética , Fator 1-alfa Nuclear de Hepatócito/genética , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteínas Repressoras/genética , Transdução de Sinais , Análise de Célula Única , Proteínas Supressoras de Tumor/genética
2.
Cell ; 149(2): 467-82, 2012 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-22500808

RESUMO

T cell development comprises a stepwise process of commitment from a multipotent precursor. To define molecular mechanisms controlling this progression, we probed five stages spanning the commitment process using RNA-seq and ChIP-seq to track genome-wide shifts in transcription, cohorts of active transcription factor genes, histone modifications at diverse classes of cis-regulatory elements, and binding repertoire of GATA-3 and PU.1, transcription factors with complementary roles in T cell development. The results highlight potential promoter-distal cis-regulatory elements in play and reveal both activation sites and diverse mechanisms of repression that silence genes used in alternative lineages. Histone marking is dynamic and reversible, and though permissive marks anticipate, repressive marks often lag behind changes in transcription. In vivo binding of PU.1 and GATA-3 relative to epigenetic marking reveals distinctive factor-specific rules for recruitment of these crucial transcription factors to different subsets of their potential sites, dependent on dose and developmental context.


Assuntos
Diferenciação Celular , Epigênese Genética , Linfócitos T/citologia , Animais , Fator de Transcrição GATA3/metabolismo , Regulação da Expressão Gênica , Estudo de Associação Genômica Ampla , Código das Histonas , Camundongos , Camundongos Endogâmicos C57BL , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas/metabolismo , Receptores Notch/metabolismo , Elementos Reguladores de Transcrição , Transdução de Sinais , Linfócitos T/metabolismo , Transativadores/metabolismo , Transcrição Gênica
3.
J Org Chem ; 89(11): 7552-7560, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38805672

RESUMO

Herein, a palladium-catalyzed diastereoselective dearomatization/cross-coupling cyclization reaction between N-arylacyl indoles and (E)-ß-chlorovinyl ketones is reported. Through this cyclization/cycloisomerization cascade, a series of furan-containing indolines were obtained in yields up to 95%. The reaction features readily accessible starting materials, benzyl Pd(II)-catalyzed cycloisomerization of (E)-ß-chlorovinyl ketones, the sequential formation of three bonds and bis-heterocycles, and excellent diastereoselectivity. More importantly, the carbene-secondary benzyl migratory insertion is proven to be a critical process in the sequential cyclizations.

4.
J Org Chem ; 89(17): 12085-12093, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39180542

RESUMO

A palladium-catalyzed domino cyclization/cycloisomerization reaction of alkyne-tethered carbamoyl chlorides with (E)-ß-chloroenones is reported. This reaction proceeds via a syn-carbopalladation of the alkyne, followed by a vinyl-PdII-catalyzed cycloisomerization of the (E)-ß-chloroenone cascade, which provides an efficient method to synthesize furan-linked methylene oxindoles. The reaction features stereodefined vinyl-PdII species, high to excellent 5-exo/6-endo selectivity, excellent Z/E selectivity, and the sequential formation of three bonds and bis-heterocycles. The strategy for the synthesis of furan-containing benzofurans has also been demonstrated.

5.
World J Surg Oncol ; 22(1): 222, 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39192318

RESUMO

AIMS: To explore rare and difficult cases of undifferentiated embryonal sarcoma of the liver (UESL) in children in a single centre, summarize the diagnosis and treatment experience and analyse the role of a computer-assisted surgery system (Hisense CAS), thus providing a new global vision and three-dimensional perspective. METHODS: We retrospectively collected the clinical data including the diagnoses and treatment processes, of children with UESL confirmed by histopathological examination in our hospital from January 2009 to December 2020. The relationship between the tumour volume and important blood vessels and between the liver volume and tumour volume, as well as other three-dimensional characteristics in the reconstructed three-dimensional model were analysed using Hisense CAS. The findings from this analysis can be used to aid in surgical decision-making and preoperative planning. RESULTS: Four children-3 girls and 1 boy-with UESL were included in the study. The age at onset ranged from 6 to 8 years. All four children presented with symptoms of abdominal discomfort, and abdominal masses were detected during physical examination. Owing to the wishes of their parents and the possibility that the disease was benign, all four children underwent one-stage radical surgery. For patient 1, a three-dimensional reconstruction was created during the initial diagnosis, which made accurate evaluation and planning of the preoperative procedure challenging. In patient 2, the tumour was located in the middle lobe of the liver and involved the first and second hepatic hilum. For patient 3, the pathological diagnosis of the tumour after surgery was challenging, but eventually, the diagnosis was confirmed through histochemistry and consultation with higher-level hospitals. Patient 4 had a giant tumour, which had a preoperative simulated future liver remnant volume (FLV) that was 21.0% of the total volume of the liver and tumour (TLTV). According to the standard liver volume (SLV) for children, the FLV was 77.0% of the SLV, making surgery feasible. All four children underwent complete resection, and only patient 4 experienced recurrence below the diaphragm 19 months after surgery. Currently, the 3-year overall survival rate is 100%, and the 3-year event-free survival rate is 75%. CONCLUSION: UESL in children is rare, and the key to diagnosis and treatment is complete surgical resection. Through individualized three-dimensional surgical planning, accurate and complete resection of difficult and complex UESL in children can be achieved, leading to a favourable prognosis.


Assuntos
Neoplasias Hepáticas , Neoplasias Embrionárias de Células Germinativas , Sarcoma , Humanos , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/cirurgia , Masculino , Feminino , Criança , Estudos Retrospectivos , Sarcoma/cirurgia , Sarcoma/patologia , Sarcoma/diagnóstico , Neoplasias Embrionárias de Células Germinativas/patologia , Neoplasias Embrionárias de Células Germinativas/cirurgia , Neoplasias Embrionárias de Células Germinativas/diagnóstico , Prognóstico , Imageamento Tridimensional , Cirurgia Assistida por Computador/métodos , Hepatectomia/métodos , Seguimentos , Tomografia Computadorizada por Raios X
6.
Pediatr Dermatol ; 40(4): 706-709, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36724903

RESUMO

CARD14-associated papulosquamous eruption (CAPE), a spectrum that includes clinical features of psoriasis and pityriasis rubra pilaris (PRP), is associated with activating mutations in the CARD14 gene. Herein we describe the clinical features of a family with CAPE and a novel mutation of CARD14, and highlight ectropion as part of the phenotypic spectrum of CAPE.


Assuntos
Ectrópio , Exantema , Pitiríase Rubra Pilar , Psoríase , Humanos , Pitiríase Rubra Pilar/diagnóstico , Pitiríase Rubra Pilar/genética , Mutação com Ganho de Função , Mutação , Guanilato Ciclase/genética , Proteínas de Membrana/genética , Proteínas Adaptadoras de Sinalização CARD/genética
7.
J Integr Plant Biol ; 65(12): 2645-2659, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37929676

RESUMO

Maize (Zea mays) requires substantial amounts of nitrogen, posing a challenge for its cultivation. Recent work discovered that some ancient Mexican maize landraces harbored diazotrophic bacteria in mucilage secreted by their aerial roots. To see if this trait is retained in modern maize, we conducted a field study of aerial root mucilage (ARM) in 258 inbred lines. We observed that ARM secretion is common in modern maize, but the amount significantly varies, and only a few lines have retained the nitrogen-fixing traits found in ancient landraces. The mucilage of the high-ARM inbred line HN5-724 had high nitrogen-fixing enzyme activity and abundant diazotrophic bacteria. Our genome-wide association study identified 17 candidate genes associated with ARM across three environments. Knockouts of one candidate gene, the subtilase family gene ZmSBT3, confirmed that it negatively regulates ARM secretion. Notably, the ZmSBT3 knockout lines had increased biomass and total nitrogen accumulation under nitrogen-free culture conditions. High ARM was associated with three ZmSBT3 haplotypes that were gradually lost during maize domestication, being retained in only a few modern inbred lines such as HN5-724. In summary, our results identify ZmSBT3 as a potential tool for enhancing ARM, and thus nitrogen fixation, in maize.


Assuntos
Estudo de Associação Genômica Ampla , Zea mays , Zea mays/genética , Zea mays/microbiologia , Nitrogênio , Polissacarídeos , Bactérias
8.
Mol Med ; 28(1): 119, 2022 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-36153499

RESUMO

BACKGROUND: This study aimed to investigate the effects of LINC00240/miR-155/Nrf2 axis on trophoblast function and macrophage polarization in the pathogenesis of preeclampsia. METHODS: Bindings between LINC00240, miR-155 and Nrf2 were validated by dual luciferase reporter assay or RNA-immunoprecipitation. Cell proliferation, migration, invasion, and pyroptosis were detected by CCK-8, clone formation, wound healing, Transwell system, and flow cytometry, respectively. Macrophage polarization was tested by flow cytometry. The expression levels of LINC00240, miR-155, Nrf2, and oxidative stress and pyroptosis-related markers in in vitro and in vivo preeclampsia models were analyzed by qPCR, western blot, or ELISA assays. Blood pressure, urine protein levels, liver and kidney damages, and trophoblast markers in placenta tissues were further studied in vivo. RESULTS: Placenta tissues from preeclampsia patients and animals showed decreased LINC00240 and Nrf2 and increased miR-155 expression levels, and the decreased M2 macrophage polarization. LINC00240 directly bound and inhibited expression of miR-155, which then inhibited oxidative stress-induced pyroptosis, promoting proliferation, migration and invasion abilities of trophoblasts, and M2 macrophage polarization. Inhibition of miR-155 led to increased Nrf2 expression and similar changes as LINC00240 overexpression in trophoblast function and macrophage polarization. Overexpression of LINC00240 in in vivo preeclampsia model decreased blood pressure, urine protein, liver and kidney damages, increased fetal weight and length, and induced trophoblast function and M2 macrophage polarization. CONCLUSION: LINC00240 inhibited symptoms of preeclampsia through regulation on miR-155/Nrf2 axis, which suppressed oxidative stress-induced pyroptosis to improve trophoblast function and M2 macrophage polarization. LINC00240 could be a potential therapeutic target for preeclampsia.


Assuntos
MicroRNAs , Pré-Eclâmpsia , RNA Longo não Codificante , Animais , Apoptose , Movimento Celular , Proliferação de Células , Feminino , Humanos , Macrófagos/metabolismo , MicroRNAs/genética , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Pré-Eclâmpsia/genética , Gravidez , Piroptose , RNA Longo não Codificante/genética , Sincalida/metabolismo , Trofoblastos/metabolismo
9.
Clin Exp Rheumatol ; 40(2): 247-253, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34528507

RESUMO

OBJECTIVES: Dermatomyositis (DM) is a systemic autoimmune disease, which typically affects the striated muscle with a variable involvement of the skin and other organs. Clinically amyopathic DM (CADM) is a combination of hypomyopathic DM (HDM) and amyopathic DM (ADM), with a characteristic of skin-predominant lesions. To date, large-scale studies on the prognostic factors of DM/CADM have been limited. The aim of this study is to evaluate the prognostic values of clinical manifestations in DM/CADM and to develop a prognostic nomogram for DM/CADM. METHODS: A development cohort (n=239), an internal validation cohort (n=128) and an external validation cohort (n=90) were included in this study. Overall survival (OS) was estimated by the Kaplan-Meier method. Univariate and multivariate Cox proportional hazards regression analyses were performed. Cox proportional hazards model and forward stepwise selection with the Akaike information criterion were used for multivariate analysis of prognostic factors. The concordance index (C-index) and calibration curve were calculated to evaluate the predictive accuracy of the proposed nomogram. RESULTS: Rapidly progressive interstitial lung disease (RP-ILD) and erythrocyte sedimentation rate (ESR) were identified as risk independent prognostic factors, with antinuclear antibodies (ANA) was identified as protective independent prognostic factors, for DM/CADM. A prognostic nomogram was formulated based on these three predictors. The C-index of the proposed nomogram in the development cohort was 0.874 (95%CI, 0.819-0.929). The predictive accuracy of the proposed nomogram was further validated in the internal validation cohort, with a C-index of 0.799 (95%CI, 0.681-0.917). Furthermore, the C-index was 0.864 (95%CI, 0.699-1.000) in the external validation cohort, indicating a good calibration ability. This proposed nomogram showed a promising predictive accuracy on the prognosis of DM/CADM. CONCLUSIONS: RP-ILD, ANA and ESR are prognostic factors for DM/CADM. The proposed nomogram based on these three factors could accurately predict the 10-year OS probabilities of patients with DM/CADM.


Assuntos
Dermatomiosite , Doenças Pulmonares Intersticiais , Estudos de Coortes , Humanos , Nomogramas , Prognóstico
10.
Proc Natl Acad Sci U S A ; 116(18): 9008-9013, 2019 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-30975761

RESUMO

Survival from malignant mesothelioma, particularly pleural mesothelioma, is very poor. For patients with breast, ovarian, or prostate cancers, overall survival is associated with increased sensitivity to platinum chemotherapy due to loss-of-function mutations in DNA repair genes. The goal of this project was to evaluate, in patients with malignant mesothelioma, the relationship between inherited loss-of-function mutations in DNA repair and other tumor suppressor genes and overall survival following platinum chemotherapy. Patients with histologically confirmed malignant mesothelioma were evaluated for inherited mutations in tumor suppressor genes. Survival was evaluated with respect to genotype and site of mesothelioma. Among 385 patients treated with platinum chemotherapy, median overall survival was significantly longer for patients with loss-of-function mutations in any of the targeted genes compared with patients with no such mutation (P = 0.0006). The effect of genotype was highly significant for patients with pleural mesothelioma (median survival 7.9 y versus 2.4 y, P = 0.0012), but not for patients with peritoneal mesothelioma (median survival 8.2 y versus 5.4 y, P = 0.47). Effect of patient genotype on overall survival, measured at 3 y, remained independently significant after adjusting for gender and age at diagnosis, two other known prognostic factors. Patients with pleural mesothelioma with inherited mutations in DNA repair and other tumor suppressor genes appear to particularly benefit from platinum chemotherapy compared with patients without inherited mutations. These patients may also benefit from other DNA repair targeted therapies such as poly-ADP ribose polymerase (PARP) inhibitors.


Assuntos
Mesotelioma/genética , Mesotelioma/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Reparo do DNA/genética , Feminino , Predisposição Genética para Doença/genética , Mutação em Linhagem Germinativa , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/mortalidade , Masculino , Mesotelioma/tratamento farmacológico , Mesotelioma Maligno , Pessoa de Meia-Idade , Platina/uso terapêutico , Neoplasias Pleurais/genética , Neoplasias Pleurais/mortalidade , Análise de Sobrevida , Proteínas Supressoras de Tumor/genética , Ubiquitina Tiolesterase/genética , Adulto Jovem
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